(1) in units of weight shall be in terms of the avoirdupois pound or ounce;

(2) in unit of liquid measures shall be in terms of the United States gallon of 231 cubic inches or liquid-quart, liquid-pint, or fluid-ounce subdivisions of the gallon, and shall express the volume at 68 degrees Fahrenheit (20 degrees Celsius), except in the case of petroleum products, for which the declaration shall express the volume at 60 degrees Fahrenheit (15.6 degrees Celsius), and except also in the case of a commodity that is normally sold and consumed while frozen, for which the declaration shall express the volume at the frozen temperature, and except also in the case of a commodity that is normally sold in the refrigerated state, for which the declaration shall express the volume at 40 degrees Fahrenheit (4 degrees Celsius);

(3) in units of linear measure shall be in terms of the yard, foot, or inch;

(4) in units of area measure shall be in terms of the square yard, square foot, or square inch;

(5) in units of dry measure shall be in terms of the United States bushel of 2,150.42 cubic inches, or peck, dry-quart, and dry-pint subdivisions of the bushel;

(6) in units of cubic measure shall be in terms of the cubic yard, cubic foot, or cubic inch; provided, that in the case of a commodity packed for export shipment, the declaration of quantity may be in terms of the metric system of weight or measure.

(b) Any of the following abbreviations for customary units, and none other, may be employed in the quantity statement on a package of commodity:

(1) Avoirdupois

avdp;

(2) Cubic

cu;

(3) Feet or foot

ft;

(4) Fluid.

fl;

(5) Gallon

gal;

(6) Inch

in;

(7) Liquid

liq;

(8) Ounce

oz;

(9) Pint

pt;

(10) Pound

lb;

(11) Quart

qt;

(12) Square

sq;

(13) Weight

wt;

(14) Yard

yd.

(1) Avoirdupois

avdp;

(2) Cubic

cu;

(3) Feet or foot

ft;

(4) Fluid.

fl;

(5) Gallon

gal;

(6) Inch

in;

(7) Liquid

liq;

(8) Ounce

oz;

(9) Pint

pt;

There normally are no periods following, nor plural forms of, these abbreviations. For example, "oz" is the abbreviation for both "ounce" and "ounces".

(c) Any of the following metric symbols may be employed in the quantity statement on a package of commodity:

(1) meter

m

(2) millimeter

mm

(3) square meter

m2

(4) liter

l

(5) gram

g

(6) kilogram

kg

(1) meter

m

(2) millimeter

mm

(3) square meter

m2

(4) liter

l

(5) gram

g

(6) kilogram

kg

(1) meter

m

(2) millimeter

mm

(3) square meter

m2

(4) liter

l

(5) gram

g

(6) kilogram

kg

(1) meter

m

(2) millimeter

mm

(3) square meter

m2

(4) liter

l

(5) gram

g

The liter is widely used for volume in preference to its equivalent, the cubic decimeter (dm3 ). Symbols are not capitalized unless the unit is derived from a proper name. Periods should not be used after the symbol. Symbols are always written in the. singular form -do not add "s" to express the plural when the symbol is used. Multiples and submiltiples of the above units and symbols may be used provided they follow the guidelines of the International System (SI) of Units or ISO Standard 1000.